What does code P2779 mean?

Q: What does code P2779 mean?

Downshift Switch Circuit Range/Performance. P2779 indicates that the transmission control module (TCM) has detected an out-of-range or performance fault in the downshift switch circuit, which is used to signal a manual downshift request in automatic transmissions with manual shift control. The TCM compares the switch input against expected voltage or signal patterns and sets this code when the signal is erratic, stuck, or outside the normal operating range.

DTC codes / P27xx · Transmission / P2779

P2779Downshift Switch Circuit Range/Performance

P2779 indicates that the transmission control module (TCM) has detected an out-of-range or performance fault in the downshift switch circuit, which is used to signal a manual downshift request in automatic transmissions with manual shift control. The TCM compares the switch input against expected voltage or signal patterns and sets this code when the signal is erratic, stuck, or outside the normal operating range.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaTransmission

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.